Spoiler Alert
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OK, I'm starting to think Locke and the MiB were linked throughout the whole series. Locke runs into the smoke monster (MiB) early on in the series, Locke helps Jack when Jack was looking for water (with the help of the MiB as the image of Jack's dad), and Locke uses the smoke monster to help Boone get his mind right when Boone wanted to tell Shannon about the hatch....it almost seems like the MiB was using Locke from the very beginning to get what he wanted.....
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A major question for me is how Locke was able to walk after the crash and Ben knew he was in a wheel chair before the crash (can't be a transition between realities after the crash or that Locke was alive and just started to walk).....really, the only explanation is that they were dead in the whole series.....I suppose one could argue that the MiB healed Locke because he had plans for him (Locke was still alive after the crash)....Ben certainly reenforced this idea throughout the series....the MiB was mad when Locke didn't turn the wheel, which triggered his ultimate death and the chance for the MiB to use Locks's image to get Ben to kill Jacob.....
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I still wonder if the writers made all these twists and turns in the plot by design, or they just kind of made things vague enough that you could come up with all these scenarios....